A) 5 cm/s
B) Zero
C) 10 cm/s
D) (d) 20 cm/s
Correct Answer: C
Solution :
Weight of the body \[W=mg=\frac{4}{3}\pi {{r}^{3}}\rho g\] \[T=\frac{4}{3}\pi {{r}^{3}}\sigma g\]and\[F=6\pi \eta vt\] When the body attains terminal velocity net force acting on the body is zero. i.e., W-T-F=0 And terminal velocity\[v=\frac{2}{9}\frac{{{r}^{2}}(\rho -\sigma )g}{\eta }\] As in case of upward motion upward force is twice its effective weight, therefore, it will move with same speed 10 cm/sYou need to login to perform this action.
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